Isolation and Characterization of Anthraquinones from The Bark of Two Cassia Species and Optimization of Dyeing Process on Wool by Their Bark Extracts

Abstract

Wool fabric has been dyed with aqueous extracts of powder bark of Cassia fistula and Cassia siamea. The dyeing characteristics of the colouring matter on wool have also been studied with or without mordants. Optimization of dyeing process for wool was done by bark extracts of both the plants. Three anthraquinones 1,8-dihydroxy-6-methoxy-3- methyl anthraquinone from the bark of Cassia fistula and 1, 8-dihydroxy- 3-methyl anthraquinone and bianthraquinone cassiamin from Cassia siamea have been isolated and characterized with help of chromatographic and spectroscopic techniques. These anthraquinones are responsible for dyeing properties in both the plants.